What's the difference between 12-year-old Cognac and 21-year-old? Until recently-as far as the consumer could tell-not much. That was because the world's premier brandy didn't have age statements on the label. Now, in a ground-breaking development, Courvoisier bottles two Cognac blends that trumpet their ages right on the bottle.

This is the first time such a move has been made by one of France's four large Cognac houses (the others are Hennessy, Martell and Rémy Martin). It was enabled by a proprietary age-tracking system created by retired master blender Jean-Marc Olivier 25 years ago (age statements reflect the youngest liquid in the blend). The anomaly of one of the world's oldest and proudest spirits is that its main grading system has been vague in describing the quality of the blend in the bottle. VS (at least two years old), VSOP (four years) and XO (six years) don't do the liquid particularly proud as almost all contain far older eau-de-vie than those claims. (In 2016, the minimum of XO will be set at 10 years to better reflect that.)

Now, Courvoisier gives a window into what sort of maturity an extra nine years produces. The 12-year-old, a blend of primarily Borderies grapes, is a sweet and friendly ingénue with a flowery presence and underlying fruit, spice and vanilla. The 21-year-old, exclusively from Grand Cognac grapes, is the grown-up version with blatant sex appeal and complexity of character. Flavor notes include insistent nuttiness, anise,tangerines, crème brulee, cinnamon, graham cracker, vanilla and the subtle whisper of roots.

Courvoisier's new issues (which will not appear in France) don't rule out exploring the other fine houses. You can be secure in the knowledge that they offer well-matured Cognac. At the XO level and above (e.g., Hennessy's Paradis, Rémy's Louis XIII, L'or de Jean Martell and L'Essence de Courvoisier) the ages extend into several dozen years. And smaller houses-e.g. L'Hommage de Pierre Ferrand, Paul-Marie & Fils Pineau des Charentes, the exquisite one-off, The Last Drop-also explore the age stratosphere.